Electric signaling system for railways.



J. S. HOLLIDAY.

ELECTRIC SIGNALING SYSTEM FOR RAILWAYS.

' APPLICATION FILED JAN. 30,,1908. 917,763. Patented Apr. 13 1909. 2 SHEETS-SHEET 1.

-- I 2% I g j H N v N N 0 1 Q N N K g Q INVENTOR 4 J; s. HOLLIDAY. ELEGTRIG SIGNALING SYSTEM FOR RAILWAYS.

APPLIOATIDN FILED JAN. 30, 190B.

Patented Apr. 13, 1909.

2 SHEETS-SHEET 2 INVENTOR 5 and 6 designate the truck ruils which,

JOHN S. HULLIDAY, OF WlLKlNSE Ulti}v P SIGNAL COMPANY, OF SWISSVALE, PENNY To (lilac/mm it may co n-car v Be it known that 1, JOHN S. HoLLrnAY, of lNilkinshurg, Allegheny county, Pennsyh vania, have invented :1 new and useful Electric Signaling- System for Esilwsys, of which the following is s lull,cle2tr, and exact description, reference being had. to the ec compztnying drawings, forming part of this specification, in .Vl1l(1h- Figures 1, "3 and 3 are diegrurnlnatic rcpresentutions showing two different embodiments of my invention.

Mv invention has signaling systems for r Ways; ond more particularly to that class oi such systems in which the truck rails, instead oi. being divided into insulated blocks or sections as in the usual practice, are electrically continuous for all currents, both propulsion and signaling. Such a system is described and broudly claimed in he pending application of L. H. Thullcn, originally filed August 22nd, 1904, Serial No. 221,773, rcnewsl liled March 5th, 1906, Serial No. 301-!362.

An object of the present invention provide means whereby the rel wh control the signaling ojcrziting circuits not be effected either by the propulsion cur rents or by currents from any other source except that which proceeds from the source which is intended to operate them.

Other objects and advantages of the invcntion will hereinafter nppeur.

The precise nature of my invention will be best understood by reference to the occompcn 'ing drawings, in which i have shown diagrammatically tWo dil'l'cront iornis thereof, and which will now be described, it bein premised, however, that the invention is susceptible of various other enil'wdiim'ents Without departing, from its s'iirit and scope as defined by the appended claims.

Referring first to the diagram shown in Fig. 1, the numerals 2, 3 and designate two-phase transmission line from which the current for operating the relays is derived.

as above stated, instead of being divided into insulated blocks or sections in the usual manner, are electrically continuous for all currents, both propulsion end signaling. The terms section and dis 'sion as cmployed herein sud in the in m therefore, refer to insulated div] ms or sec tions of rails, hut urc merely used for "'lution to eleriisic s, do not,

eonenience to designate the portions of the rnch between adjacent signals. These rails re supplied with a two-phase current derived. from the two-phase transmission line through the two-phase trunsf :mers 7 and 8, one transformer being shown for each of the tire truck sections or divisions illustrated. These trzuislormers each huve'two secondary soils or windings 9 and 10, the coil 9 being itQ/i hi the coil ill oeing connectedito the mil 5. The other it inols of th e two coils ere i conductorl l, ie four relays d by the respective 15, there being two numerals 12, lb, l-l u" of these relays shown ror esch t l-eel: section or division. Erich relay hes two coils or windings l5 and 1?, the coil lfi'being-connerted by one termir to the rail 6 end the coil 17 heing connected to the 5. 18 designates the movable hers of these relays, loco; sign nw circuit 19 throuqh the contucts 128. The two sets of contacts 20 for -vh t ch: section or di"'ision are in series h a 1 other, she v11. 21 end 22 design-awe the respective senmphores s 'or the respective truck sections or 39 in the usual rnanuerz he operation is as follows 'lhe movable 18 of the relays when no trains are in the divisions hold the contacts 20 closed, and the semaphores or sigaiiuls 21 and at ()pOlzli to close the local circuits and clear the rent u -i Y oug coils they o' ien and it v never the co s lo eil' rely. It will be seen that While coils i6 and 17 of each relay are in parallel "h 6 and 3.7, hile i le danger cease to not relation to euch other with respect to the.

transformer of the Sit-I119 truck section or division, so that each con or winding will carry one phase of the current impressed upon the trail; rails by the transformer, yet shut by reason of their connection to the common res urn conductor 13 lending to the coinni.

one terminal to the rail fi, z ne.

which are arranged to control thewhich signals are controlled by the i us. That is to say, these relays the unction of the secondury coils of the o 'mis when positively actuated by curthe currents from any othertransformer, ex-

- them, it will be readily ceptthe one which is intended to operate seen that the relays will not be affected in any way" by stray cur rents fromany source and that they will only operate by a two-phase current from their own transformer. Supposing a train-tube traveling from right to left and halving a clear track ahead, as the train approaches the relay 15 that relay. will be short-circuited,

and the signal 22 will be set at clan er. Inasmuch as the contacts controlled y the two rela s14 and 15 are in'series with each other in t e local signaling circuit, it will be seen that the signal 22 will remain at danger so long as either of these relays is sho1't circuited by-the train, or in other words, while the train is in that division, since itis' always between the transfornier and one of the relays.

, The-train will retain its control of the relay 14 until it gains control of the relay 13.,y5rifter it has gained control of the relay 13 '1t will lose'its control of the relay 14 and the signal 22 will clear. As soonas the train'gains control of the relay 13, the signal'2]. will be set at danger, and will remain at clan ger so long as the train is in that section or division of the track and controlling either of the relays 12 and 13.

It will be understood that the relays can be adjusted or tuned so that trains'will retain and lose control thereof at any desired distance therefrom, this depending u )01) the impedance of the rails, the power factor of the system, and various other conditions well known tosignal engineers and which must be determined by them in each case in accord-v ance with the usual practlce.

-. Inasmuch as there is no exactly defined points in the track which separate adjacent .sectlons or divisions thereof, there Wlll neeessarily be some overlap which will make it necessary to set the signals somewhat in ad control-"of the relay lii by Vance of the rail definingpoints of the divi- 810111801 sections, so that the signal guarding the entrance to any nn-tic'ular section or divisionwill not go-to danger in the face of the danger at such time as the train. That is to say, the signal 21 will go to train. has gained.

thfatrelay', and the signal 21 must be set sufwillhave passed 'or to I that ficien'tly behind the relay 13 so that the train the time it gainscontro of said relay.

The arrangement shown in Fig. 2 is similar shown in. Fig. '1, except that instead loying a twokphasc transmission line, 0y a single-phase transmission line 23 single phase transformers 24. The

of em I emp with have shown each track section or division portion thereof, with an intermediate trans- Xvhere electric ployed as the short-eircuiting be passing said signal at secondaries of each of these transformers are connected with the respective track rails 5 and 6 by a branched circuit 25 and 26, one of these branches, as the branch 25, having therein a capacity 27, and the other branch havil'ig an impedance coil, or other impedance device, 28. By this arrangement the current delivered by the secondaries of the transformers will be split into a twophase current, one phase of which will be delivered to each of the track rails in the same manner as in the arrangement shown in Fig. 1. .'lhe relays in this case are threephase relays having each two'coils 16 and 17 arranged in the saline manner the coils .16 and 17 of the relays first described and l'laving a third coil or winding 29 which is connected (.lirectly across the 'two-phase transmission line 23, the purpose of this third coil or winding being to reduce the power required for operating the relays to be transmitted over the rails. The other parts of the system shown in Fig. 2 not specifically referred to are designated by the same refer ence numerals as the corrospomling parts in the system of Fig. 1.

1n the arrangements above described, I

as provided with two relays, one at each end former. in the arrangement shown in Fig.

3, however, there .is but one relay for each track section or division, the transformer being placed near the entrance to the division, and the relay near the opposite end. This relay is shown at 30 and the transformer at 31. 32 indicates diagrammatically a train in one of the divisions. The other numerals are the same as those employed in Fig. 1 to designate corresponding parts.

The advantages of my invention are many, and will be apparentto those skilled in the art. The use of the track rails Which are electrically continuous for all currents avoids the necessity for the expensive eross-bomling which is required in t 1e old block systems propulsion is employed. The relays are of simple character together with the circuits therefor, and are of such character, as before described, as to be absolutely unaffected by any currents except those which are intended to operate them; Either direct or alternating current may be empropulsion current.

l. clann:-

1. In an electric signaling system, track railswhich are electrically continuous for all currents, means fidr impressing polyphase currents on said rails, and signal-controlling relays connected to the rails, each relay having windings which'are in parallel with respect to the currents impressed upon the track rails of the particular division of the track to which that relay is connected, but which. are in series with respect to any propulsion current which,

impressed upon other pulsion current which may flow therethrough, and also with respect to currents impressed u on other adjacent portions of the rails; su stantially as described.

2. In an electric signaling system, track rails which are electrically continuous for all currents means for impressing two-phase currents? n said rails, and signal-controlling relayskohnected to the rails, each relay having windingswhich are in parallel with respect to the currents impressed upon therack rails of theparticular division of the track to which that relay is connected, but which are in series with respect to any promay flow therethrough, and also with respect to currents adjacent portions of the rails; substantially as described;

3. In an electric signalihg system, track rails which'are electrically continuous for all currents, means for impressing two-phase currents upon the rails, and signal-controlling relays having two coils connected one to each track rail and both connected to a common return conductor leadingto the source of their operating current; substantially as described. r I

4. In an electric signaling system, track rails which are electricall continuous for all currents, a plurality of rel ays for each signal, a transformer for each signal, and means whereby each transformer'impresses' a twophase current uponltheadjacent"portions oi the track rails, each relay having two coils which are connected by one terminal to different track rails, and by' their other terminals to a common return to the secondary of. the transformer substantially as described. 5.; In an'electric signaling system, track rails which are electrically continuous for all. currents, aplurality of relays for each signal, a transformer for each signal, and means whereby each transformer impresses a two phase current upon the adjacent portions of l v the track rails, each relay h aving' two coils which are connected by one terminal to dif-' the other winding connected to nals to a common return to the secondary together with a signal circuit for each signal controlled in said circuit;

'currents,,transformers for impressing twophase currents on said rails, and signal-controlling relays each of which has two windings which are in parallel with their own transformer, but which are in series with each other with respect to thecircuit of other transformers; substantially as described.

7. .In an electric signaling system, track rails which are electrically continuous for'all for impressing two-phase currents, means ays, said relays havingtheir concurrents upon said rails, one of said rails carrying one phase of the current, rail carrying the other ph and suitable controlling and the other ase ol' the current, relays having each two windings which are connected across the track rails inseries, and also by a common returnconductor with the source of their operating current, all the relays focany particular track division having their signal-controL stantially asdescribed.

8'. In an electric signaling system, track rails electrically continuous l'or all currents, a two-phase relay and a source of two-phase ling contacts in series with each other; subcurrent in each block, said relay having one of its windings connected to said source by one track rail and a common return wire, and said source by the opposite track rail and the common return wire; substantially as described.

In testimony whereof, I have hereunto set my hand.

JOHN S. HOLLIDAY.

Witnesses' -z A. E. HOLMAN, W. H. McOLELLANn, Jr. 

